Tuesday, February 9, 2010

At AirJaldi's rural wireless networks in the Himalayas, all routers have PoE or Power over Ethernet supplying their power needs. PoE technology uses the same regular ethernet cable you may use at home, and then sends POWER (electricity) over that cable along with the data. (more about PoE and an $8 implementation.)

This simplifies the wiring of your wireless mesh (no power cords necessary) and provides a way for custom wireless routers to supply power to peripheral devices with embedded PoE converters. In this way, wireless routers can become a power as well as information "hub". Simply applying Occam's Razor to the twin problems of rural electricity and communication, we immediately perceive that supplying them both simultaneously is the most simple solution.

The IEEE standard 802.3at for world-wide use of PoE also enables the creation of complex "smart grid" IP-enabled green electrical networks, which will be highly useful for scalable and "bottom-of-the-pyramid" approaches to Green Energy.

Saturday, February 6, 2010

Wi-fi mesh is the best choice available, now, for grassroots global connectivity. Even though the mesh is resistant to attack and shut-down, however, it can still be disrupted by large-scale radio frequency interference that floods Wi-Fi's specific operating channels. Similarly, normal interference from other mesh network devices crowding into Wi-Fi's channels can degrade your signal and severely affect the mesh.

Some of this spectrum interference can be avoided with a combination of directional antennas and modified routing protocols that take a "web of trust" approach to whom can participate in the mesh. But the long-term answer to these concerns is to design your network as a "Cognitive Mesh".

Cognitive Mesh uses "intelligent" router nodes, which can sense which frequencies around it are currently congested or being blocked, and switch the frequency they use accordingly. This technology is very experimental and under world-wide, active research- but it could make large-scale wireless networks very fast, highly reliable, and simultaneously almost impossible to destroy through interference.

"As the radio spectrum usage paradigm moves from the traditional command-and-control allocation scheme to the open spectrum allocation & access scheme, wireless networks meet new opportunities and challenges. Accordingly, we introduce the concept of cognitive wireless mesh networking (CogMesh) and address the unique problems in such a dynamically networking environment. Basically, CogMesh is a self-organized distributed network architecture combining cognitive wireless access technologies (e.g. Cognitive Radio) with the mesh (ad-hoc) structure in order to provide an integrated & converged service platform over a wide range of heterogeneous networks." - Honggang Zhang's laboratory at Zhejiang University

As this description notes, cognitive mesh networks basically combine 2 technologies, Cognitive radio and Wireless Mesh, into a single seamless integration. It is necessary from a commercial perspective, in order to provide very large-scale mesh networks where many people are sharing the same channel frequencies. And it is also necessary to prevent disruption by authoritarian regimes wishing to shut-down free speech and stifle protesters.

Therefore, the use of cognitive mesh networks, particularly cognitive mesh networks with Wi-Fi, is a means by which to create a robust, grassroots technology of direct peer-to-peer communication that cannot be easily shut down by repressive governments.

Mesh networks are a new type of connectivity paradigm. Generally, when talking about wireless internet connectivity, individual are either "passive consumers" or "commercial providers". For example, when you are sitting at a coffee-shop, browsing the internet on a Wi-Fi wireless hotspot, you can only exchange information with your friend across the table by going first to the Wi-Fi hotspot's router and then to your friend. In other words, the Wi-Fi hotspot is the "provider" and you are just the "consumer" or client attached to that hotspot.

However, mesh networks turn this command-and-control schema on its head, by turning every individual connected to the network into a "provider" of internet connectivity. This makes mesh internet incredibly resistant to repressive regimes (please see previous post for more info and pictures of mesh networks.) To take the coffee-shop example up again, you could now send information directly to your friend sitting across the table, without going through any intermediate Wi-Fi hotspot routers, since you yourself are an internet provider in a mesh network. By directly connecting to your friends, and agreeing to pass along their messages in exchange for them passing along yours, a grassroots internet network of potentially very high speeds (<500 Mbps) is created.

There have already been many practical, large-scale wireless Wi-Fi mesh networks established in places all over the planet, and there is shared expertise and experience as a result of this fact.

Many free and open source software packages are already available for setting up and running a Wi-fi network.

Wi-Fi also shares the general advantages of wireless over wired communication, like-

No cost for laying wires and cables.

Easy to deploy in short amount of time

Relatively cheap hardware relative to commercial mobile equipment

Simple to shift coverage or expand your wireless range

Wi-Fi mesh networks are inherently decentralized, and that makes them stay functional even if power cuts or technical problems prevent some nodes from working properly. This is a major concern, especially in a developing country with poor electricity infrastructure. A mesh can simply "route around" these problem nodes, and the messages still get out.

This decentralization also makes mesh networks difficult to censor or shut down. See a forthcoming post about making Wi-Fi mesh networks even more resilient against repressive governments through the use of the "Cognitive" mesh.

Friday, February 5, 2010

The Freifunk community announced last week that it had successfully deployed 5 wireless mesh networks in 5 different towns in Afghanistan, connecting local schools and libraries to the internet and each-other.

Freifunk uses Wi-Fi, the ubiquitous coffee-shop and home wireless solution, to create large-scale "mesh" networks that share wireless spectrum amongst each-other and can connect to the larger internet. A mesh network (technically, ad hoc mobile network) is newer form of wireless network that has the potential to be transformational as a grassroots, non-centrally-controllable communication platform for the global citizens movement.

A mesh is not formed by any central wireless tower (which could be easily shut down by authorities in repressive regimes) but instead arises naturally from many people directly connected to their local neighbors. Messages, video, pictures and the internet in general can be accessed by anyone in the mesh, just by jumping from one person directly to the next, in a chain, until you reach the person or website you want.

Mesh nets are resistant to being attacked, since they can just route the messages along a different chain if a particular node is knocked out or shut down. The messages still get out. For this reason, mesh networks are known as "self-healing", because they route around obstacles and attacks.

Without the media (pictures, video, first-hand testimonials) and the medium (the internet) the message is obscured and more easily manipulated or ignored.

Reporters without Borders has published a useful handbook for bloggers and cyber-dissidents detailing how to blog from a place on Earth which is tightly censored. It includes things like how to circumvent censors, use proxy servers to disguise your true IP address, and other interesting strategies.

But how do you deal with governments who shut down the entire network? Even the Burmese military was able to shut down the whole system once they realized the effect the bloggers were having on world perception of the protest and crackdown. Again, we must have independently powered and inconspicuous methods for reaching the larger Network. The only option I'm aware of is satellite broadband internet connections. Do you know of a better one? Comment it in.

Barring another option, how can we make satellite broadband connections work on a large scale in a rural environment?

The Problems Waiting to be Solved:

1) Electricity. How do you run these satellites in villages with no regular power?
2) The Platform. How do you link cheap mobile phones, cameras or laptops with the satellite?
3) Cost. Who's paying for the satellites and the peripherals like the platform?
4) Vulnerability. How do you avoid retaliation from the authorities for having a satellite dish?
5) Delivery. How do you get these satellites into the country?

The first three problems are shared by rural education programs, while the last two are unique to repressive governments. Any ideas for solutions or criticisms of the satellite method, let's hear them.

Tuesday, October 16, 2007

Forget free markets or Marx. The real power behind these systems lies in the network.

Today's society is based on the master-slave mindset. Some humans work very little and gain much, while most work constantly and gain little or nothing. Warfare, psychological stress and violence result. This model is inherently unstable and must eventually collapse for humanity to reach spiritual equilibrium in a more fair and equitable global world. So let's break it down to the fundamentals.

The Global Citizens Movement demands three things for every human:

1) Health2) Freedom3) The Network

Health includes food, medicine and a clean environment. Freedoms encompass everything that does not harm another being, like freedom of expression, freedom to move freely across the earth, and the freedom to pursue your dreams.

The final demand of the Global Citizens Movement is access to the Network, which is an informal term for an efficient communication system linking millions of humans across the globe. This is currently most similar to the Internet, which allows anyone, anywhere, to access the full spectrum of human knowledge instantly and cheaply. The Network allows global citizens to create cheap business models, bypass middlemen and distributors, and most importantly, tap into limitless information. Have you ever heard someone observing a new gadget remark "what will they think of next?" Increase the pool of inventors by a few hundred million and see what they say then.

Take a big picture view of the planetary phase of civilization. In this new era, the real divide is between the urban and rural. Urban cities will have the easiest time transitioning into a global citizens movement since they already (usually) have better access to medicine, doctors, and internet connections. The real choke point, however, is the villages.

Rural villages across the world don't need dimly lit factories and call centers. They don't need to migrate into vast shantytowns in mega-cities. The point is, once the Network penetrates fully into the villages-- they won't have to. E-learning, online conferencing, telemedicine, direct-to-consumer agricultural sales, and a hundred thousand thousand similar possibilities are waiting for Network penetration. You could be born a farmer's son in rural Nepal and still study economics. That same young man could work for an international consulting firm, or publish microcredit analyses, or find the best prices and distributors for his father's harvest. He could do all this, and more, through the Network, since the Network destroys traditional barriers like distance and the accident of birthplace. It is a new planetary paradigm unfolding before our eyes.

This blog will focus on one highly important obstacle to the Global Citizens Movement-- the lack of universal network access-- and the ways we might bypass traditional, expensive and impractical ways to link villages with the internet.